JPH0125831Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a valve for liquids, for example, a valve that is attached to a drain pipe of a reaction vessel and used as a stop valve or a throttle valve.

BACKGROUND ART AND PROBLEMS A valve of this type as shown in FIG. 2 is known. The valve box 1 of this valve has a valve seat 2 at the upper end.
A hole 3 coaxial with this is provided at the lower end, and a valve stem 4 is slidably fitted into this hole 3. A seal 5 is attached between the valve box 1 and the valve stem 4 by a seal presser 6. However, in this case, the valve stem 4 is
Therefore, the gasket 5 cannot be tightened very strongly, making it difficult to completely prevent liquid from leaking from the hole 3. In addition, corrosive liquids such as hydrochloric acid are often passed through this type of valve, and in this case, a glass lining or the like is applied to the inner surface of the valve body 1 and the outer peripheral surface of the valve stem 4. The surface of the rod 4 becomes rough, making it even more difficult to prevent liquid leakage.
Such liquid leakage not only causes a loss of liquid, but also causes the liquid flowing down along the valve stem 4 to interfere with the operation of the air cylinder 7 and the like, causing a failure. This is particularly true for corrosive liquids.

Additionally, there are known general valves in which a bellows or the like is attached between the valve stem or valve body inside the valve box and the valve box or lid (for example, Utility Model Publication No. 13-10986). , Japanese Patent Publication No. 53-125628,
(Refer to Japanese Patent Application Laid-open No. 128027/1983). However, in such conventional valves, the end of the bellows is fixed to the valve stem or valve body and cannot be removed, making maintenance difficult. The whole thing needs to be replaced.

The purpose of this invention is to solve the above-mentioned problems and provide a valve that is free from leakage and easy to maintain.

Means for Solving the Problems The valve according to this invention has a liquid inflow opening with a valve seat at the upper end of the valve box, and a liquid outflow opening at the tip of a portion extending obliquely downward from the side of the valve box. An opening is provided, and a valve stem is vertically slidably fitted into a hole provided in the lid of the opening in the lower part of the liquid inflow opening of the valve box, and the upper end of the valve stem protrudes above the valve seat. In a valve equipped with a valve body, the valve stem consists of a shaft to which the valve body is fixed at the upper end, and a nut that is fitted over the part of the shaft below the valve body and screwed into the part of the shaft below that. The part of the cylinder passes through the hole in the lid, and the part of the cylinder inside the valve body of the valve stem is fitted with a retractable sealing tube, and the part of the tube passes through the hole in the lid. The outward flange formed around the entire circumference of the lower end is sandwiched between the inner surface of the lid and the valve box in a watertight manner, and the inward flange formed around the entire upper end of the sealed tube is attached to the upper end of the valve stem cylinder. It is characterized by being held in a watertight manner between the valve body and the valve body.

In this specification, upper and lower refer to the state of use shown in FIG. 1.

Embodiment Hereinafter, one embodiment of this invention will be described with reference to FIG.

The valve includes a valve box 10 made of cast iron or steel that is open at both the upper and lower ends and at the tip of a portion extending diagonally downward from the side, and each open end, that is, the upper end opening (liquid inflow opening) 10a, Lower end opening 1
Flanges 11, 12, and 13 are formed at the ends of 0b and side opening (liquid outflow opening) 10c, respectively. The upper opening 10a of the valve box 10 is provided with a valve seat 14 made of Teflon (tetrafluoroethylene resin), which is made separately from the valve box 10, and the annular stepped portion 15 formed at the lower opening 10b is provided with a valve seat 14 made of Teflon (tetrafluoroethylene resin). A stainless steel disk-shaped lid 16 is fitted from below. The lid 16 is fastened to the valve housing 10 by bolts 18 and nuts 19 passed through its flange 17 and the flange 12 of the valve housing 10, and its inner surface forms an outward facing flange 3 at the lower end of a sealed tube 31, which will be described later.
3, and is pressed against the stepped portion 15 through the hole 3. Further, the lid 16 is provided with a hole 20,
A valve stem 21 is slidably fitted into this hole 20. The valve stem 21 has a stainless steel shaft 25 that has threaded portions 22, 23, and 24 at three locations at both the upper and lower ends and a portion near the middle lower end, and is fitted over most of this shaft 25 to cover the lid 16. A stainless steel cylinder 26 passes through the hole 20, and a steel valve body 27, which protrudes above the valve seat 14, is screwed to a male threaded portion 22 at the upper end of the shaft 25. and,
A cylinder 26 fitted to the shaft 25 is connected to two nuts 28 and 29 screwed into the male threaded part 24 in the middle.
As a result, it is fixed in pressure contact with the lower end surface of the valve body 27 via an inward flange 32 at the upper end of the sealed tube 31, which will be described later. Note that a wrench hooking prismatic portion 30 is formed between the male threaded portion 23 at the lower end of the shaft 25 and the male threaded portion 24 above it. In addition, a portion of the cylinder 26 of the valve stem 21 inside the valve body 10 has a cylinder 26.
A bellows-shaped sealed tube 31 made of Teflon having an inner diameter approximately equal to the outer diameter of 6 is fitted over the tube, and a horizontal inward flange 32 is formed around the entire upper end of the sealed tube 31, and a horizontal inward flange 32 is formed around the entire lower end of the sealed tube 31. A horizontal outward flange 33 is formed. The inward flange 32 at the upper end of the sealed tube 31 is
It has an inner diameter approximately equal to the inner diameter of the cylinder 26, and the valve stem 21
A valve body 27 and a cylinder 26 are attached to the shaft 25 of the valve body 27 and are clamped between the valve body 27 and the cylinder 26 to maintain watertightness between the outer circumference of the valve stem 21 and the sealed pipe 31. On the other hand, the outward flange 33 at the lower end of the sealed tube 31 is connected to the lid 16.
It has an outer diameter that is approximately equal to the outer diameter of the inner surface, and when the lid 16 is tightened to the valve box 10, it is held between the annular stepped portion 15 of the valve housing 10 and the inner surface of the lid 16, and the hole 2
0 and between the valve box 10 and the lid 16 are kept watertight. In addition, in the hole 20 part of the lid 16,
A packing box is formed, and a gland packing 34 is attached to this part by a packing presser 35.
The posture of the valve stem 21 is maintained stably. moreover,
A plurality of connecting rods 36 are attached to the outer surface of the lid 16 facing downward, and an air cylinder 37 for driving a valve body is fixed upward to the lower ends of these rods 36.
The piston rod 38 of the cylinder 37 has a rectangular column portion 39 formed at its upper end, into which the male threaded portion 23 at the lower end of the shaft 25 of the valve rod 21 is screwed and fixed with a nut 40. Further, the cylinder 37 is provided with a bracket 41, and a limit switch 42 for detecting the lower end position of the valve body 27, that is, the valve closing position is attached to this bracket 41. The operating plate 43 of the limit switch 42 is fixed to the upper end of the piston rod 38 by the nut 40 mentioned above.
The surface of the valve body 27 and the inner surface of the valve box 10 are lined with glass.

This valve is arranged, for example, between a drain hole provided at the bottom of the reaction vessel and a drain pipe. That is,
The flange 11 of the upper end opening 10a is attached to the flange of the drain hole, and the flange 13 of the side opening 10c is attached to one end of the drain pipe in a watertight manner. Then, the valve is closed by moving the valve body 27 downward by the cylinder 37, and opened by moving the valve body 27 upward, and the liquid flows into the valve box 10 from between the valve body 27 and the valve seat 14. flows into. The liquid flowing in from the upper end opening 10a passes through the inside of the valve box 10 and enters the side opening 1.
0c, the entire upper end of the sealed pipe 31 is attached to the outer periphery of the valve stem 21 in a watertight manner, and
Since the entire lower end is attached in a watertight manner around the hole 20, and the space between the valve stem 21 and the lid 16 is always sealed, there is no risk of liquid leaking between them. Moreover, since the sealed pipe 31 is bellows-shaped and is expandable and retractable, it does not hinder the vertical movement of the valve stem 21. The reaction vessel is normally filled with a liquid in which crystals are dissolved, but since the inside of the reaction vessel is constantly stirred, even when the valve is closed, there is no liquid near the valve body 27 that protrudes into the reaction vessel. No crystals will precipitate. On the other hand, when the valve closes, the liquid flowing into the valve box 10 flows out from the side opening 10c.
There is no possibility that liquid will accumulate near the valve body 27 in the valve box 10 and crystals will precipitate. Therefore, crystals do not precipitate and interfere with the opening and closing of the valve.

The valve box, valve seat, lid, valve stem, valve body, sealed pipe, air cylinder, etc. are not limited to those of this embodiment, and can be modified as appropriate. For example, in the above embodiment, an annular recess where liquid accumulates is formed above the outward facing flange 33 at the lower end of the sealed tube 31, but in order to eliminate such a liquid pooling recess, the outward facing flange is formed. The inner portion of the portion 33 may be thickened upward. Furthermore, this valve is not necessarily arranged so that the valve stem 21 is vertical.

Effects of the invention As described above, according to the valve of this invention, the valve box 1
Since the telescopic sealed tube 31 is watertightly attached between the valve body 10, the lid 16, and the valve stem 21, there is no risk of liquid leaking between the valve body 10, the lid 16, and the valve stem 21. Both the inward flange 32 at the upper end of the sealing tube 31 and the outward flange 33 at the lower end are located between the cylinder 26 of the valve stem 21 and the valve body 27 and the lid 1.
6 and the valve box 10, if the sealing tube 31 is damaged, it can be easily removed and replaced, reducing maintenance. It's easy.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing one embodiment of this invention, and FIG. 2 is a partially cutaway front view showing a conventional example. 10...Valve box, 10a...Top opening (opening for liquid inflow), 10b...Lower end opening, 10c...Side opening (opening for liquid outflow), 14...Valve seat, 16...
... Lid, 20 ... Hole, 21 ... Valve stem, 25 ... Shaft,
26... cylinder, 27... valve body, 28, 29... nut, 31... bellows-shaped sealed tube, 32... inward flange, 33... outward flange.

Claims (1)

[Claims for Utility Model Registration] A liquid inflow opening 10a having a valve seat 14 is provided at the upper end of the valve case 10, and a liquid outflow opening 10c is provided at the tip of a portion extending diagonally downward from the side of the valve case 10. A valve stem 21 is vertically slidably fitted into a hole 20 provided in the lid 16 of the opening 10b in the lower part of the liquid inflow opening 10a of the valve box 10. In a valve provided with a valve body 27 protruding above the seat 14, the valve stem 21 is attached to a shaft 2 to which the valve body 27 is fixed at the upper end.
5, and a cylinder 26 that is fixed by nuts 28 and 29 that are fitted over the part of the shaft 25 below the valve body 27 and screwed into the part of the shaft 25 below, and the part of the cylinder 26 is The cylinder 2 passes through the hole 20 of the lid 16 and is located inside the valve body 10 of the valve stem 21.
A telescopic sealing tube 31 is fitted over the portion 6, and an outward facing flange 33 formed around the entire lower end of the sealing tube 31 is sandwiched between the inner surface of the lid 16 and the valve box 10 in a watertight manner. A valve characterized in that an inward flange 32 formed around the entire upper end of a sealed tube 31 is held between the upper end of a cylinder 26 of a valve stem 21 and a valve body 27 in a watertight manner.